Efficient methylene blue dye degradation via visible light-activated g-C3N4/CuO nanocomposites

Abstract

In this work, pure and heterostructured g-C₃N₄/CuO photocatalyst materials were prepared using a combination of thermal decomposition and hydrothermal techniques. The phase and purity of the catalysts were examined using powder X-ray diffraction (XRD). The prepared catalysts were also assessed using different systematic techniques, which demonstrated that the addition of CuO to the g-C₃N₄ matrix significantly altered the particle size, crystallinity, morphology, and energy bandgap. Heterojunction formation and interfacial contact between CuO and g-C₃N₄were confirmed by TEM and XPS analyses. The photocatalytic activity of the g-C₃N₄/CuO nanocomposite was assessed by its ability to break down Methylene Blue (MB), an organic contaminant, under visible-light exposure. Remarkably, the g-C₃N₄/CuO catalyst demonstrated rapid photocatalytic degradation of MB, achieving 98 % breakdown within 40 min. The increased degradation efficiency of g-C₃N₄/CuO is due to its lower energy bandgap, enhanced charge transport, and lower charge recombination compared to pure CuO and g-C₃N₄. Therefore, constructing a g-C₃N₄/CuO heterostructure could be a promising technique for sewer water treatment.